


Latent Variable

by Bitenomnom



Series: Mathematical Proof [47]
Category: Sherlock (TV)
Genre: Friendship, Kissing, M/M, Sensory Overload, Sherlock tastes things, dinner at Angelo's
Language: English
Status: Completed
Published: 2012-12-04
Updated: 2012-12-04
Packaged: 2017-11-20 06:49:10
Rating: Not Rated
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,317
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/582480
Author URL: https://archiveofourown.org/users/Bitenomnom/pseuds/Bitenomnom
Summary: <blockquote class="userstuff">
              <p>“John,” he pulled himself into a sitting position to face John. “How many times have you seen me eat outside this flat?”</p><p>	John leaned back thoughtfully. “Well, I…” He tilted his head. “Huh.” John scooted forward in his chair, leaning over his knees to look Sherlock in the eye. “Why?”</p><p>	“It’s more comfortable.” </p><p>	“Is that it? You starved yourself of a nice hot dinner at Angelo’s so that you could sit on the sofa while you eat?”</p><p>	“That’s not it.”</p><p> </p><p>Sherlock never eats at restaurants when he and John go out -- not even when he's not on a case.</p>
            </blockquote>





	Latent Variable

**Author's Note:**

> Well, (1) I was going to write this for today no matter what math happened, because I got the idea in my head and couldn't shake it, but (2) I feel like I didn't quite do the idea justice, so...yeah. Still, I hope you like it...? And (3) if the math connection seems tenuous, given (1), you know why. XD (Also, I had very little to work with, since a lot of what we did was sort of a rehashing of the nested dichotomies.)
> 
> Also of possible interest to anyone who has been reading this prior to yesterday (12/3) and therefore won't have seen a link on the piece, who also doesn't follow me on Tumblr: last night I did some art for Maximum Cooperation (you know, the one where John puts a mic in Sherlock's room...?). Warning: NSFW!! It's [here](http://toasterfish.tumblr.com/post/37106422302/drawing-of-a-scene-from-maximum-cooperation-in).
> 
> Additionally for any of you who don't follow me on Tumblr, a couple days ago I did a little Sherlock Mad Lib thing in celebration of getting 200 followers, where a Mad Lib story summary I made was filled out by a number of participants with my promise that I'd write a fic to fit the result. So in case you want a preview of what's to come (when I have some time...), [here's the summary](http://toasterfish.tumblr.com/post/37019854939/the-mad-lib-results). I'm really quite frightened. @_@ But I will really really truly actually do it.

The three main types of model that can be used for categorical variables with more than two possible responses are the polytomous logit model, the [Nested Dichotomy](http://archiveofourown.org/works/577168), and the proportional-odds model. The least of these is used only in situations where the categories in question are ordinal, i.e. can be put into some sort of natural order. (For instance, some sort of spectrum, e.g. low-income, middle-income, high-income.) This model involves creating a latent variable (it is invisible—we don’t see it) that is used to break up the range of responses into the various categories. (For instance, if the value of the latent variable falls within a certain range, that point belongs to the second category.)

***  
  
            “We’re not even on a case,” John said through a mouthful of lasagna. They’d popped up to Angelo’s for the evening, Sherlock insisting that after all the running about they’d done earlier that day, John ought to eat as much as he’d like to ensure he’d be in top shape tomorrow. Lestrade had hinted that he might need to bring Sherlock in on a particularly nasty double-homicide soon. “And you said we might be working again tomorrow. You should eat now.”

            “I’ll eat later,” Sherlock waved John off.

            “We’re at a _restaurant_ right now,” John insisted. “You know, those places designed for the sole purpose of sitting down and eating.” He paused. “Though, come to think of it, Angelo didn’t even ask you what you wanted.”

            Sherlock shrugged. “He knows I don’t eat when I’m here.”

            “And he’s not, I dunno, insulted?” John scooped up another mouthful of pasta.

            “No.”

            “I figured before it was always just because he saw you were on a case.”

            Sherlock glanced out the window, remembering dashing out the door for what he’d figured was a lost cause anyway, because of something that definitely wasn’t a lost cause—John regaining full use of his leg, the pain abating. They’d been back here a number of times since, but this was the first time since then that they’d sat at the same table as they had that night. John had stopped complaining about the candles on the tables, possibly because he’d caught the way Angelo’s eyes shone whenever he and Sherlock came in and sat down, and couldn’t bear to argue with that face.

            “He knows we come in here for you to get something to eat,” Sherlock finally explained. “Not me.”

            “But why not you?” John leaned forward a little, speaking more gently for fear of sounding like he was attacking Sherlock. “You _have_ to be hungry. I don’t care how much a waste of time you think eating is; you need to do it.” He paused. “You even look a little lightheaded.”

            Sherlock did feel lightheaded, dizzy, but it wasn’t just the hunger. He closed his eyes and gripped at the table, using its texture to ground himself.

            “Sherlock?” John said quietly. He tentatively laid his hand on the back of Sherlock’s. “Are you okay?”

            “I’ll eat later,” he said again, not opening his eyes.

            “Should I ask Angelo to let us take something back?”

            Sherlock shivered. “If you want more, certainly, but if I were you I’d just come back and get it fresh.”

            “I meant for you.”

            “No need.”

            “Sherlock,” John prompted him, and stroked his fingers along the back of Sherlock’s hand. “What’s wrong?”

            “I’ll tell you later.”

            “Okay,” John said quietly. “Okay.”

 

 

 

            When they had settled in at the flat, John hesitated in front of the refrigerator with the small box of food Angelo had let him take back with him. “Will you tell me why you didn’t want to eat before?” John closed the refrigerator, box still in hand. “And don’t say you weren’t hungry.”

            “I am,” Sherlock admitted. John carried the box over to the sofa, where Sherlock was lounging, and set it on top of the journals on the table before taking a seat in his chair.

            “Right,” John said. “So then…”  
            “John,” he pulled himself into a sitting position to face John, glancing for a moment at the box on the table. “How many times have you seen me eat outside this flat?”

            John leaned back thoughtfully. “Well, I…” He tilted his head. “Huh.” John scooted forward in his chair, leaning over his knees to look Sherlock in the eye. “Why?”

            “It’s more comfortable,” was all Sherlock said, through a slightly tightened throat.

            “Well, sure, but…” He shifted a bit. “I mean…is that it? You starved yourself of a nice hot dinner at Angelo’s so that you could sit on the sofa while you eat?”

            “That’s not it.”

            John waited.

            Sherlock reached out and touched the box, prodding the corner to spin it in place. “There’s so much data,” he finally said.

            “Well, while you’re on a case, but—”

            “Information existing isn’t restricted to times when Scotland Yard is being particularly stupid,” Sherlock snapped, “nor to times when idiot in-laws steal family heirlooms.” He took in a deep breath. “It’s always there.”

            “Sure,” John said, and Sherlock recognized it as a cue to explain further, a ‘Sure’ followed by a silent ‘but…’

            “People, each with their own lives, their own clothes, having conversations with their own voices about trivia or death or anything else between, their little habits, finger-tapping, quick blinking—doors, swinging in, creaking, the temperature gradient created by the draft of air, fonts on the menus, silverware of varying compositions of metals and states of cleanliness, clattering, chairs scraping along the floor, squabbles among the staff, mistakes made in the kitchen—and everything sharpened by hunger, and all before the scents of each dish being walked past the table or cooked up in back—how can you take it all in without the thought of _eating_ making you nauseous?”

            “And eating makes it worse because…”

            Sherlock shook his head. “How am I meant to process something so excruciatingly intense as taste while still processing everything else?” He looked up at John, who was broadcasting either confusion or pity, neither of which was something Sherlock could deal with at that moment. “Never mind; you don’t understand.”

            “Well, no,” John admitted. “But we’re here, now. So you can eat that.” He nodded toward the box. “And,” he added, more quietly, “thanks for telling me. Even if I don’t really…well. Of course I don’t get it; just like I don’t get half the other things you say.” He smiled hesitantly. “Doesn’t mean you’re wrong, or that I don’t believe you.”

            “Hm,” Sherlock said, still deep in thought.

            “Sherlock?”

            “What?”

            “You can have that,” John nodded at the box. “I brought it back for you.”

            “I don’t want it.”

            “Why not?”

            Sherlock sighed. “Too…different.”

            “You’re gonna have to explain that.”

“Eating new things takes a great deal more effort than it’s worth, for, at best, more frustration than the alternative.”

            “And at worst?”

            “Exposed nerves,” Sherlock said, which John knew shouldn’t make nearly as much sense to him as it did. He was reminded of jerking awake in the middle of the night and still feeling wind blowing against him, not on his skin but directly against his bones, or maybe a little deeper than that, leaving no time for him to think, jumping straight onto his spine and up the back of his neck in a blink.

            “Okay.” He stood up and sat beside Sherlock on the sofa. “Sure. But…we have Thai and Chinese and Indian all the time. Those are about a hundred times more overwhelming than a bit of alfredo.”

            “My mother very frequently brought one of those three home, when I was young,” Sherlock said. “I can’t remember a time before curry.”

            John glanced around the flat. “Right. I…I sort of get it. So you don’t want to eat something new even at the flat, because…it’s still pretty overwhelming.”

            “Right,” Sherlock said. “Not worth the effort or stress, for something so dull and tedious as eating.”

            “Mm,” John said, this time, and simply sat shoulder-to-shoulder with Sherlock for a few minutes, considering the box. “Sort of like still being able to hear bombs going off when you’re in a bunker,” he said, finally. Sherlock looked to him. “I was trying to imagine how, being in a safe place, you’d still feel overwhelmed eating something different.”

            “Oh,” said Sherlock, quietly. “Yes. Like that.” He met John’s eyes, and found an unexpected level of understanding there.

            “If you wanted to, though…” John started, and hesitated. “Well, if you wanted to try some of what I brought home…I’ve got a bit of an idea.”

 

 

 

            Sherlock could feel the push of the blindfold against the curls of his hair as John reached around behind his head to tie it, could sense the warmth emanating from John’s arms and, from directly in front of him, John’s body.

            “What else?” John whispered.

            “Sound.”

            “I need to be able to talk to you,” John started to argue, before exhaling slowly at the way that Sherlock quirked his eyebrows. “Okay, but we need a system. Er, you can talk to me, obviously…”  
            “I’d rather not.” He specified, “Distracting.”

            “Okay. So, I’ll be sitting here like this…can you find my shoulder?”

            Of course he could. Sherlock reached out to touch it. He drew back quickly when he found it bare.

            “Er, sorry,” John said. “I thought the rustling might distract you—you mentioned clothes before—so I, er, stripped down to my pants, since you’re blindfolded anyway. But if we’re putting in earplugs, I can…”

            “No,” Sherlock said, “it’s fine. I don’t mind.” He considered it. “In fact, I think that would help me, to do that as well.”

            “Oh,” John said. “Er. Okay. Just so you know, though, I’m not blindfolded like you are, so…”

            Sherlock shrugged, and pulled his shirt off. “Reducing the number of textures against my skin should be helpful,” was all he said. John was quiet for a few moments as Sherlock removed the remainder of his clothing—including his pants. “I hope I haven’t offended you,” Sherlock said dryly in response to John’s silence.

            “No,” John said. “Just…never mind.”

            “We were discussing a system so that we could both avoid speech,” Sherlock prompted. Maybe this wasmore trouble than it was worth.

            “Okay, just…tap my shoulder twice if you’re uncomfortable, okay? And I’ll give you a moment. If I tap your shoulder once, it’s me asking how you’re doing.”

            “I’ll tap you once back for ‘okay,’” Sherlock said. “But do avoid it if you can help it.”

            “’Course,” John said. “Just want to be safe, though.”

            “I _am_ capable of removing a blindfold and earplugs if it becomes too much.”

            John smirked, though he knew Sherlock couldn’t see him. “Right, you’ve got some earplugs in your room, then?”

            “Yes,” Sherlock said. “Use the green ones; they’re less likely to be contaminated.”

            “Not going to ask.” Sherlock felt the sofa move beneath him as John got up to retrieve them.

            When Sherlock had fitted the plugs into his ears, John tapped his shoulder. Sherlock sighed and reached out to tap John back.

            The next thing Sherlock felt was warmth near his mouth. He opened it slowly and one small forkful of lasagna was conveyed into it; Sherlock closed his lips around it and felt the fork slide out.

            Without light and sound assaulting him, Sherlock’s mind did not resist being snapped into sharp focus around the bite of lasagna, although he tightened one hand around his leg to remind himself that he was still in his body, not hurtling through space-time at immeasurable speeds as it strove to calculate and categorize the texture of the noodle and the acidity of the sauce and the spices in the meat while still pleading to drop the onslaught of sensation like a hot iron in his hands. Sherlock felt John reach for the hand gripping his leg and take it in his own, and rather than contributing to the overload, the feeling grounded Sherlock further, distracted him just enough to replace the hot iron with something just a little cooler.

            He bit back the impulse to simply swallow the stuff down without chewing, and worked his tongue around it as his teeth closed down, feeling the taste burn into his tongue like the sun did into others’ eyes, too bright for him to discern color or pattern or anything other than _look away, look away_ , but he squinted into it and squeezed John’s hand as he chewed and then swallowed.

            John tapped his shoulder once.

            Sherlock hesitated. This wasn’t ‘ _okay_ ;’ he wasn’t ready for more of it. But he wasn’t ready to stop, either—not that he had found the lasagna delicious, or that he particularly wanted to try to—what would they call it— _‘fix’_ —whatever part of him resisted it—but he wasn’t sure he was ready to give up this moment with John, to take this gesture, this effort on John’s part, and dismiss it as if it were nothing. He could try again. “I need to cool down,” he muttered, and felt John jump slightly at the sound. “Can I taste something less painful for a while?” After a traumatic injury, the brain blocked sensations of pain. Perhaps if he continued tasting things, it would do the same for his tongue.

             “Tea?” John offered quietly, taking his hand off of Sherlock’s, presumably to reach for his mug.

            Sherlock nodded, and took John’s mug when he felt it brush against his hands. He took a few lovely, familiar sips. Tea and coffee were godsends, so familiar to him that he could drink them anywhere, conducive to the application of calories in the form of cream and sugar and therefore suitable substitutes for meals when he was away from the flat for long periods of time. Some called stews or steak and kidney pie “comfort food”—for Sherlock it was tea and coffee.

            After a few minutes, he held the mug back out to John, who took it and set it back on the table.

            Sherlock tapped his shoulder once.

            Shortly thereafter, another bite, a little cooler in temperature, came to his mouth. As Sherlock bit his teeth around the fork, he could sense, almost _feel_ John’s hand on the fork, his fingers maybe an inch or two away from Sherlock’s mouth, warm and reassuring. John’s other hand took Sherlock’s again.

            He breathed heavily through the initial flood of sensation, loud as a bustling pub against his tongue, popping like little flecks of fireworks, fiery and bright in his mouth. Taste remained on his tongue even as he moved the lasagna to the other side of his mouth, eating into it like echoes of acid and stinging sharp shouts. Sherlock gulped it down.

            John tapped his shoulder once.

            After a minute of stillness and silence on Sherlock’s part, Sherlock felt John release his hand as he reached back for the tea.

            He grabbed for the hand.

            “John,” he mouthed. Like everything else about John, John’s name was comforting. Sherlock could wrap his lips around it easily, just like he could so easily rely on John to follow him into danger, to whisper small praises at Sherlock’s deductions amidst accusations of _psychopath_ and _freak_. John was just the right temperature; John was just the right name. John was the realization that John wasn’t the only one who was walking with a limp when they met; John was the difference between, “What’s wrong with you?” and “How can I help you?” that Sherlock had never had the opportunity to consider before John.

            Sherlock wasn’t quite ready for more lasagna, but he wasn’t ready for John to retreat thinking he hadn’t succeeded in anything at all. He wasn’t ready for John to up and leave, not when he was here, so close to Sherlock, so comforting and so right in so many ways.

            He reached out for John’s shoulder, laying his hand on it and then running it down his arm until reaching his hand. Sherlock let his fingers run along the fingers that John had used to grasp the fork, and then gently wrapped his own hand around them. Slowly, slowly enough that John could pull away, if he wanted, Sherlock pulled John’s hand toward him, and then tentatively took John’s fore- and middle fingers into his mouth.

            Like wrappers or faint scents at crime scenes, John’s flavor was faint and indirect enough to be unintimidating; like _tom yum kung_ , when the flavor soaked through, it felt _correct_ , warm and familiar and like it belonged there. Perhaps he had lived with John long enough now, been close enough to him for long enough, that his mind had already catalogued John’s scent as _belonging_ , and so taste wasn’t such a far stretch. Sherlock couldn’t think quickly enough to restrain an, “Mmmph.” When John seemed to hesitate at the sound and began to pull his fingers out, Sherlock grabbed his hand and held it there, sucking at his digits for just a few moments more before slowly releasing John’s hand.

            Although he expected it, he lamented the loss of John’s fingers when John pulled them back out. What he did not expect was for John to offer something else up near Sherlock’s face; Sherlock opened his mouth slightly and waited for John to lift it in.

            It was John’s lower lip.

            Impulsively, fearing the possibility of its premature absence, Sherlock sucked it into his mouth, bit it gently—like John’s fingers, but tangier with the faint taste of blood from John’s lip, still healing from when it had been split against his teeth in a fistfight with an arsonist a few weeks ago. He sucked in John’s tongue, too, which still tasted very faintly, very manageably, of the lasagna—which, from this perspective, was not quite so bad, perhaps—and Sherlock endeavored to strip that taste away to get to only that of John’s tongue; he sucked harder.

             John yanked his head back and tapped Sherlock’s shoulder twice. He cupped his hands around the sides of Sherlock’s face, and with his forefinger and thumb, pulled out Sherlock’s earplugs.

            A rush of sounds met Sherlock’s ears: faint background noises of the flat, someone in the adjacent building listening to music, the heater running, and, most notably, John’s slightly labored breathing.

            “Was that for tasting,” John started, “or for something else?”

            Sherlock lifted the blindfold from his eyes; he _had_ to see John in order to answer this. John’s face was flushed, not only with exertion but also with something less directly physical. Sherlock glanced over him. Well, he concluded, after a sweep up and down John’s body: maybe equally directly physical.

            “Both,” Sherlock finally said.

            John seemed to find this amusing. “Yeah? How do I taste?” he laughed out a high-pitched, nervous giggle.

            “Better than the lasagna,” Sherlock said, letting his quiet tone carry his pitch deeper. “Like…vindaloo.”

            “I taste like vindaloo?”

            “No!” Sherlock huffed. “Of course not! It was an _example_.”

            John rolled his eyes. “So in other words, you don’t know?”

            “I hardly have a comprehensive overview upon which to base my analysis,” Sherlock said.

            “Oh,” John said—well—mouthed, possibly lacking the control over his breathing necessary to expel air in such a fashion that it made noise. He glanced toward the lasagna.

            “I’m done with that.” Sherlock loomed over John, evaluating regions from which to sample before making any serious attempts at answering John’s question.

            “I’m sure you’re still hungry.”

            Sherlock dipped his head to take a deep breath beside John’s neck.             John stutter-gasped at Sherlock’s proximity, at the feeling of a lot of skin against a lot of skin as Sherlock pushed up closer to him, naked.  “I’ll eat some toast later,” Sherlock rumbled, “if you let me taste something else right now.”

            “Sure,” John shivered. He leaned to the side to kiss Sherlock’s neck. “Whatever you want.”


End file.
